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Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers

Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig1

Temperature controller for walk-in coolers and freezers, type AK-RC 204B and AK-RC 205C

Warnings

  • Using the unit without observing the manufacturer’s instructions may alter the appliance’s safety requirements. Only probes supplied by Danfoss should be used for the unit to operate correctly.
  • From -40 – +20 °C, if the NTC probe is extended to 1000 m with at least 0.5 mm2 cable, the maximum deviation will be 0.25 °C
  • It should be installed in a place protected from vibrations, water and corrosive gases, where the ambient temperature does not exceed the value indicated in the technical data.
  • For the reading to be correct, the probe should be used in a place without heat influences apart from the temperature you want to measure or control.
  • IP65 protection degree is only valid with the protection cover closed.
  • IP65 protection degree is only valid if the cables enter the device using a tube for electric conductions + gland with IP65 or above. The size of the glands should be suitable for the diameter of the tube used.
  • Do not spray the unit directly with high-pressure hoses, as this could cause damage.

IMPORTANT

  • Before starting the installation, you must take the advice of local regulations in force.
  • The AUXILIARY relays are programmable, and their operation depends on the configuration.
  • The function of the digital inputs depends on the configuration.
  • The recommended currents and powers are the maximum working currents and powers.

Wiring

Always disconnect the power supply to do the wiring.
The probes and their cables should NEVER be installed in a conduit together with power, control or power supply cables.

  • For disconnection, the power supply circuit must be equipped with a switch of at least 2 A, 230 V, located near the device. The power supply cable will be H05VV-F or NYM 1×16/3. The section to be used will depend on the local standard in force, but must never be less than 2.5 mm2.
  • Cables for relay or contactor outputs should have a section of 2.5 mm2, allow working temperatures equal to or over 70 °C and be installed with as few bends as possible.
  • The 120/230 V~ wiring must be kept clear of any other external element.
  • The wiring to be done depends on the type of installation. Use the appropriate diagram based on the option selected in the wizard. Check the available options on the diagrams included in the controller’s packaging.
  • Wizard refers to a built in tool to guide the user through the set up process.

Maintenance

  • Clean the surface of the unit with a soft cloth, water and soap.
  • Do not use abrasive detergents, petrol, alcohol or solvents, as this might damage the unit.

Keypad

  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig16Pressing it for 3 seconds activates/deactivates Stand-by mode. In this mode, regulation is paused and the icon is displayed. In the programming menu, this exits the parameter without saving changes, returns to previous level or exits programming.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig17Pressing once displays the temperature of probe S2 for 10 seconds (If it is enabled).
    Pressing it for 3 seconds starts/stops the defrost.
    In the programming menu, this allows scrolling around the different levels, or, during the setting of a parameter, changing its value.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig18Pressing it for 3 seconds activates/deactivates continuous cycle mode.
    In the programming menu, this allows scrolling around the different levels, or, during the setting of a parameter, changing its value.
  • Pressing once activates/deactivates the cold room light.
    Pressing it for 3 seconds accesses the condensed programming menu.
    Pressing it for 6 seconds accesses the expanded programming menu.
    In the programming menu, this accesses the level shown on the display or, during the setting of a parameter, accepts the new value.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig20Pressing once displays the current effective value of the Set Point, taking into consideration temporary modifications by other parameters (C10 or C12).
    When an alarm is underway, pressing once mutes the acoustic alarm. Pressing for 3 seconds accesses the Set Point setting.

Indicators

  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig2Fixed: Stand-by mode activated. Regulation is paused.
    Flashing: Controlled shutdown process for the regulation underway.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig3Fixed: Cold room door open.
    Flashing: The door has been open for a greater time than has been defined in parameter A12.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig4There is an active alarm, but not an active HACCP alarm.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig5Fixed: HACCP alarm active.
    Flashing: HACCP alarm registered and unconfirmed. Press the key to confirm an HACCP alarm.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig6Fixed: Evaporator fans active.
    Flashing: The evaporator fans should be active but a delay is preventing this.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig7Fixed: The cold solenoid is active.
    Flashing: The solenoid should be active but a delay or protection is preventing this.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fi8Fixed: Compressor active.
    Flashing: The compressor should be active but a delay or protection is preventing this.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig8Defrost relay active.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fi9Continuous cycle mode active.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig9Cold room light active.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig10Alarm underway muted.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig11 Temperature displayed in ° Fahrenheit / ° Centigrade.
  • Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig12Programming mode active.

STAND-BY
If the temperature regulation cannot be instantly stopped due to its configuration, a controlled stop process starts and the icon flashes. To stop the controlled stop process and force the step to Stand-by, press the Stand-by key again for 3 seconds.

Initial configuration

The first time the unit receives the power supply, it will enter into ASSISTANT mode. The display will show the message flashing with 0.

Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig13

Step 1:
Select the most suitable InI option based on the type of installation to be carried out and press SET. The available options will be shown in the following table:

 

InI

Type of installationParametersDiagram to be used
Cold regulationPump DownDefrostEvap. fansPdo00I00I10I11I20I21d1d7F3
0Demo Mode: it displays the temperature but does not regulate the temperature or activate relays
1SolenoidNoElectricYes0*200002000A
2Solenoid + compressorYesElectricYes11271002000B
3Solenoid + compressorNoElectricYes01200002000B
4SolenoidNoAirYes0*100002011A
5Solenoid + compressorYesAirYes11171002011B
6Solenoid + compressorNoAirYes01100002011B
7Solenoid + compressorYesHot gasYes1127191520C
8Solenoid + compressorNoHot gasYes0120091520C
9Solenoid + compressorYesReversed cycleYes1127100530D
10Solenoid + compressorNoReversed cycleYes0120000530D
11SolenoidNoStaticNo0*10000201A
12Solenoid + compressorYesStaticNo1117100201B
13Solenoid + compressorNoStaticNo0110000201B

* o00=2 in AK-RC 204B, o00=0 in AK-RC 205C
Note: If options 2, 5, 7, 9 or 12 are chosen, check the configuration of parameter I11 according to the pressure switch type used. (See diagram included with the device).

Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers-fig15

Step 2:
Use keys and to enter the desired Temperature Set Point value and press SET. The wizard has finished.
The unit will begin to regulate the temperature.
If this is not the first time you use the wizard, after completing the last step the display will show the
message dFp (default parameters). You may choose between two options:
0: Only changing the parameters which affect the wizard. The other parameters will remain the same.
1: All parameters return to their factory setting except those which have been modified by the wizard.

Important: The wizard will not reactivate. To enter the wizard mode, initiate Stand-by mode by pressing the key for 3 seconds and wait until the unit completely halts the temperature regulation (the indicator will light up permanently) and press the following keys in sequence one after the other, , , SET.
Warning: If the pump down function is active, a certain amount of time may elapse between starting the stand-by function and the controller stopping.

Configuration

Condensed programming menu
Enables the rapid configuration of the most frequently-used parameters (SP, C1, d0, d1, d4, F3, A1 and A2). Press the SET key for 3 seconds to access it.

Extended programming menu
Use the extended programming menu to configure all of the unit’s parameters in order to adapt it to installation requirements. Press the SET key for 6 seconds to access it.
Important:

  • If the function of the password has been configured as a keypad block (b10=2), or as an access block to parameters (b10=1), you will be requested to enter the access code programmed in PAS when attempting to access either of the two functions. If the entered password is not correct, the unit will go back to showing the temperature.
  • Certain parameters or menus may not be visible depending on the configuration of the rest of the parameters.

Regulation and control

Level 1Level 2DescriptionValuesMin.Def.Max.
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

rE

SPTemperature setting (Set Point)°C/°F-500.099
C0Probe 1 calibration (Offset)°C/°F-20.00.020.0
C1Probe 1 differential (Hysteresis)°C/°F0.12.020.0
C2Set Point top locking (it cannot be set above this value)°C/°FC39999
C3Set Point bottom locking (it cannot be set below this value)°C/°F-50-50C2
 

C4

Type of delay for the protection of the compressor:

0=Minimum time of compressor in OFF

1=Minimum time of compressor in OFF and in ON in each cycle

 

0

 

0

 

1

C5Protection delay time (Value of the option selected in parameter C4)Min.00120
 

C6

COOL relay status with fault in probe 1:

0=OFF; 1=ON; 2=Average according to last 24 h prior to probe error

3=ON-OFF according to prog. C7 and C8

 

0

 

2

 

3

C7Relay time in ON in the event of probe 1 failure

(If C7=0 and C8≠0, the relay will always be disconnected in OFF)

Min.010120
C8Relay time in OFF in the event of probe 1 failure

(If C8=0 and C7≠0, the relay will always be connected in ON)

Min.05120
C9Maximum duration of the continuous cycle mode. (0=deactivated)H.0048
 

C10

Variation of the Set Point (SP) in continuous cycle mode. When it reaches this point (SP+C10), it reverts to the normal mode. (SP+C10 ≥ C3).

The value of this parameter is always negative, unless it is 0. (0=OFF)

 

°C/°F

 

0

 

-50

 

C3-SP

C12Variation of the Set Point (SP) when the change Set Point function is active. (SP+C12 ≤ C2) (0= deactivated)°C/°FC3-SP0.0C2-SP
C19Maximum start time from Pump Down

(Values between 1 and 9 seconds will not be accepted) (0=deactivated)

Sec.00120
C20Maximum time for pump down (0= deactivated)Min.0015
 

C21

Probe to be displayed: 0=All probes (sequential)

1=Probe 1 (Cold Room), 2=Probe 2 (Evaporator), 3=Probe 3 (According to I20)

 

0

 

1

 

3

C22Stop fans and compressor on opening door 0=No, 1=Yes001
C23Start-up delay for fans and compressor with door openMin.00999
C27Probe 3 calibration (Offset)°C/°F-20.00.020.0
EPExit to level 1

Defrost

Level 1Level 2DescriptionValuesMin.Def.Max.
 

 

 

 

 

 

 

 

 

dEF

d0Defrost frequency (Time between 2 starts)H.0696
d1Maximum defrost duration (0=defrost deactivated)Min.0*255
 

d2

Type of message during the defrost:

0=Displays the real temperature; 1=Displays the temperature at the start of the defrost; 2=Displays the dEF message

 

0

 

2

 

2

d3Maximum duration of the message

(Time added at the end of the defrost process)

Min.05255
d4Final defrost temperature (by probe) (If I00 ≠ 1)°C/°F-508.050
d5Defrost on connecting the unit:

0=NO First defrost according to d0; 1=YES, First defrost according to d6

001
d6Delay of the defrost start on connecting the unitMin.00255
d71)Type of defrost:

0=Resistors; 1=Air/fans, 2=Hot gas; 3=Reversal of cycle

0*3
d8Count of time between defrost periods:

0=Total real time, 1 =Sum of compressor connected time

001
d9Drip time when completing defrost (Shutdown of compressor and fans)Min.01255
EPExit to level 1

* According to wizard.

1) It can only be modified using the configuration wizard (InI).

Evaporator fans

Level 1Level 2DescriptionValuesMin.Def.Max.
 

 

 

 

FAn

F0Shutdown temperature of fans°C/°F-504550
F1Probe 2 differential if fans are shut down°C/°F0.12.020.0
F2Shut down fans when the compressor shuts down: 0=No, 1=Yes001
F3Status of the fans during the defrost: 0=Shut down; 1=Running001
F4Delay of start-up after defrost (If F3=0) It will only actuate if it is higher than d9Min.0299
EPExit to level 1

Alarms

Level 1Level 2DescriptionValuesMin.Def.Max.
 

 

 

 

 

 

 

 

 

AL

A0Configuration of the temperature alarms: 0=Relative to SP, 1=Absolute011
A1Alarm for maximum in probe 1 (It should be higher than the SP)°C/°FA29999
A2Alarm for minimum in probe 1 (It should be lower than the SP)°C/°F-50-50A1
A3Delay of temperature alarms in the start-upMin.00120
A4Delay of temperature alarms from the end of a defrostMin.0099
A5Delay of temperature alarms from when the A1 or A2 value is reached03099
A6Delay of the external alarm/Severe external alarm on receiving a signal in digital input (I10 or I20 = 2 or 3)Min.00120
A7Delay of external alarm deactivation/Severe external alarm deactivation when the signal in digital input disappears (I10 or I20 = 2 or 3)Min.00120
A8Show warning if the defrost ends for maximum time: 0=No, 1=Yes001
 

A9

Relay alarm polarity

0= Relay ON in alarm (OFF without alarm); 1= Relay OFF in alarm (ON without alarm)

 

0

 

0

 

1

A10Differential of temperature alarms (A1 and A2)°C/°F0.11.020.0
A12Delay of open door alarm (If I10 or I20=1)Min.010120
EPExit to level 1

Basic configuration

Level 1Level 2DescriptionValuesMin.Def.Max.
 

 

 

 

 

 

bcn

b00Delay of all functions on receiving power supplyMin.00255
b01Cold room light timingMin.00999
b10Function of password

0=Inactive, 1=Block access to parameters, 2=Block keypad

002
PASAccess code (Password)0099
b20MODBUS address00247
b21Communication speed:

0=9600 bps, 1=19200 bps, 2=38400 bps, 3=57600 bps

bps023
b22Acoustic alarm enabled: 0= No, 1=Yes011
UntWork units: 0=°C, 1=°F011
EPExit to level 1

Inputs and outputs

Level 1Level 2DescriptionValuesMin.Def.Max.
 

 

 

 

 

 

 

 

 

 

 

In0

I00Connected probes

1=Probe 1 (Cold room), 2=Probe 1 (Cold room) + Probe 2 (Evaporator)

122
 

I101)

Configuration of digital input 1

0= Deactivated, 1=Door contact, 2=External alarm,

3=Severe external alarm, 4=Change of SP, 5=Remote defrost,

6=Defrost block, 7= Low pressure switch, 8=Remote Stand-by

 

0

 

*

 

8

I11Polarity of the digital input 1

0=Activates on closing contact; 1=Activates on opening contact

0*1
 

 

I20

Configuration of digital input 2

0= Deactivated, 1=Door contact, 2=External alarm, 3=Severe external alarm, 4=Change of SP, 5=Remote defrost, 6=Defrost block, 7=Register probe, 8=Probe 2° evaporator2), 9=High pressure switch for Hot Gas, 10=Remote Stand-by

 

 

0

 

 

0

 

 

10

I21Polarity of the digital input 2

0=Activates on closing contact; 1=Activates on opening contact

001
 

o001)

Configuration of relay AUX1

0=Deactivated, 1=Compressor/Resistor sump, 2=Light, 3=Virtual control,

4=Alarm3)

 

0

 

*

 

4

 

o10

Configuration of relay AUX22)

0=Deactivated, 1=Alarm, 2=Light, 3=Virtual control, 4=Door frame resistance, 5=Defrost 2° evaporator, 6=Same as solenoid status, 7=Same as unit status

 

0

 

2

 

7

EPExit to level 1

According to

  1. It can only be modified using the configuration wizard (InI).
  2. 2) Not available in AK-RC 204B
  3. Available in AK-RC 204B only

HACCP alarm

Level 1Level 2DescriptionValuesMin.Def.Max.
 

HCP

h1Maximum temperature of HACCP alarm°C/°F-509999
h2Maximum permitted time for activation of the HACCP alarm (0=Disabled)H.00255
EPExit to level 1

Information (reading only)

Level 1Level 2DescriptionValuesMin.Def.Max.
 

 

 

 

tid

InIOption chosen in the configuration wizard
Pd1)Pump down active? 0=No, 1=Yes
PUProgram version
PrProgram revision
bUBootloader version
brBootloader revision
PArParameter map revision
EPExit to level 1

It can only be modified using the configuration wizard (InI).

Messages

MessagesAR
PdPump down malfunction error (Shutdown)
LPPump down malfunction error (Start-up)
E1/E2/E3Probe 1/2/3 failure (Open circuit, crossed circuit or temperature outside the limits of the probe) (Equivalent limits in °F)ŸŸ
Ad0Open door alarm. Only if the door stays open for a greater time than is indicated in parameter A12ŸŸ
AHMaximum temperature alarm in control probe. The temperature value programmed in A1 has been reachedŸŸ
ALMinimum temperature alarm in control probe. The temperature value programmed in A2 has been reachedŸŸ
AEExternal alarm activated (by digital input)ŸŸ
AESSevere external alarm activated (by digital input)ŸŸ
AdtDefrost alarm concluded due to time-out. The time established in d1 has been exceeded
HCPHACCP alarm. The temperature has reached the value of parameter h1 during a longer period than has been established in h2ŸŸ
hCP + PFHACCP alarm due to a fault in the power supply. The temperature established in h1 has been reached following a fault in the power supplyŸŸ
dEFIndicates that a defrost is being performed
PASAccess code (Password) request. See parameters b10 and PAS
S1 – S2Shown sequentially with the temperature: The controller is in demo mode, the configuration has not been made.

A: Activates the acoustic alarm

R: Activates the alarm relay

Technical specifications

FeaturesSpecifications
Power supply230 V~ ± 10%, 50 Hz ± 5%
Maximum input power in the operation6.3 VA
Maximum nominal current15 A
Relay SSV / DEFROST – SPDT – 20 ANOEN60730-1: 15 (15) A 250 V~
NCEN60730-1: 15 (13) A 250 V~
Relay FAN – SPST – 16 AEN60730-1: 12 (9) A 250 V~
Relay COOL – SPST – 16 AEN60730-1: 12 (9) A 250 V~
Relay AUX 1 – SPDT – 20 ANOEN60730-1: 15 (15) A 250 V~
NCEN60730-1: 15 (13) A 250 V~
Relay AUX 2 – SPDT – 16 ANOEN60730-1: 12 (9) A 250 V~
NCEN60730-1: 10 (8) A 250 V~
No. of relay operationsEN60730-1:100.000 operations
Probe temperature range-50.0 – +99.9 °C
Resolution, setting and differential0.1 °C
Thermometric precision±1 °C
Loading tolerance of the NTC probe at 25 °C±0.4 °C
Working ambient temperatureAK-RC 204B-10 – +50 °C
AK-RC 205C-10 – +45 °C
Storage ambient temperature-30 – +60 °C
Protection degreeIP 65
Installation categoryII s/ EN 60730-1
Pollution degreeII s/ EN 60730-1
 

Control device classification

Built-in assembly, with Type 1.B automatic operation action feature, for use in clean situations, logical support (Software) class A and continuous operation. Degree of contamination 2 acc. to UNE-EN 60730-1.

Double isolation between power supply, secondary circuit and relay output.

Temperature during ball-pressure testAccessible parts: 75 °C

Parts which position active elements: 125 °C

Current of radio jamming suppression tests270 mA
Voltage and current as per EMC tests207 V, 17 mA
Type of assemblyFixed internal
MODBUS addressShown on label
Dimensions290 mm (W) x 141 mm (H) x 84.4 mm (D)
Internal buzzerYes

Ordering

Controller

ModelDescriptionCommentsCode no.
AK-RC 204BAK-RC 204B Gen. 2,5 O/P, Single phaseIncludes:

•     1 x 1.5 m, NTC 10K sensor

•     1 x 3 m, NTC 10K sensor

080Z5001
AK-RC 205CAK-RC 205C Gen. 2,5 O/P, Single phase080Z5002

Accessories (for spares and replacement purposes):

NameFeaturesQtyCode no.
3.5 m, NTC 10K SensorThermo plastic rubber probe1084N3210
8.5 m, NTC 10K sensorThermo plastic rubber probe50084N3208
1.5 m, NTC 10K sensorStainless steel probe150084N3200

 

Documents / Resources

Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers [pdf] Installation Guide
AK-RC 204B, AK-RC 205C, AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers, AK-RC 204B, Temperature Controller for Walk-in Coolers and Freezers, Temperature Controller, Controller
Danfoss AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers [pdf] Installation Guide
AK-RC 204B, AK-RC 205C, AK-RC 204B Temperature Controller for Walk-in Coolers and Freezers, Temperature Controller for Walk-in Coolers and Freezers, Controller for Walk-in Coolers and Freezers, Walk-in Coolers and Freezers, Coolers and Freezers, Freezers
Danfoss AK-RC 204B Temperature Controller For Walk In Coolers And Freezers [pdf] User Guide
AK-RC 204B, 205C, AK-RC 204B Temperature Controller For Walk In Coolers And Freezers, Temperature Controller For Walk In Coolers And Freezers, Walk In Coolers And Freezers, Coolers And Freezers, Freezers
Danfoss AK-RC 204B Temperature Controller for Walk in Coolers and Freezers [pdf] Installation Guide
AK-RC 204B, AK-RC 205C, AK-RC 204B Temperature Controller for Walk in Coolers and Freezers, AK-RC 204B, Temperature Controller for Walk in Coolers and Freezers, Controller for Walk in Coolers and Freezers, Coolers and Freezers, Freezers
Danfoss AK-RC 204B Temperature Controller for walk in Coolers and Freezers [pdf] User Guide
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References

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